Wild horses rarely suffer from lameness unless they are injured in some way. This is true mainly due to the fact that they are constantly on the move, run on uneven ground, stand in water and otherwise are exposed to environmental factors which wear away the hoof in the manner in which nature intended. The hoof mechanism in its natural state is designed to be a shock absorber as well as a vital aid to the circulatory system. When in motion, on contact with the ground surface, the digital cushion is compressed between the pastern bone and the sensitive frog and redirects the remainder of the force outwards and upwards to the lateral cartilages (attached to the sides of the coffin bone). The foot will expand and the sole will widen, this expansion absorbs shock and also permits the coffin bone to lower which in turn brings blood flow to the area. As the foot is lifted in stride it contracts forcing the blood out of the foot and up the leg as the foot hits the ground on the next stride. Not only does the entire structure of the foot benefit from increased circulation this process is fundamental for the health and well being of the horse.
Domesticated horses are not so lucky. They are exposed to much less uneven terrain and spend a great deal more time confined to stalls where movement is prohibited as the average stall is 11′×11′. They are protected from the more harsh and abrasive aspects of nature. Furthermore, special feeds which create other desirable conditions in domesticated horses may have a harmful effect on the feet. Therefore, it has long been recognized that special care is required to maintain domesticated horses' feet in proper condition. Horseshoes are used for this purpose.
Traditionally over the years most domesticated horses have been and are currently shod with shoes made of metal such as steel or aluminum alloys. Horseshoes are typically secured to hooves by nails. The nails pass through holes in a horseshoe and are driven into the horn wall of the hoof, known as the keratinous portion of the hoof. Great care must be taken in directing the nail into the keratinous portion so as to prevent injury to the horse. The nails are driven at an angle away from the center of the hoof, the nail points extend through the outer side wall of the hoof where they are cut off and clinched or hammered against the hoof.
Aluminum alloys are most commonly used today in racing and are characterized by efficient application, relatively low weight and expense. Horses engaged in competition training or racing are commonly re shod every three to six weeks depending on the individual's hoof growth. This is done in consideration of the weakened clinches (nails), but primarily by the desire to maintain healthy geometry with respect to the configuration of the foot and so facilitate optimal biomechanics, or way of going. As a result of the natural flexion and movement of the foot over time the nails work loose and the clinches become raised, which can often lead to a horse dislodging a shoe or shoes. This event can result in damage to the hoof wall when the clinched nails are pulled through the wall of the hoof or more disastrous if the shoe is not pulled off cleanly the horse may step on exposed nail ends damaging the sole or frog or further damage a leg with the dislodged shoe.
Frequent removal and reattachment of shoes makes numerous nail holes in the hoof walls. There is always a possibility of error when driving a nail, if driven too close to the white line it can be very painful for a horse leading to lameness and possibly abscesses. If there is insufficient new healthy horn growth two problems arise. First, with numerous nail holes already in the hoof wall, it can be difficult or sometimes impossible to secure a new shoe. Second, the abundance of nail holes lets in bacteria, dries out the hoof wall, damages the corium (vascular tissue that supplies nourishment to the hoof) and generally weakens the hoof structure, which can lead to failure of the wall and damage to the horse's hoof and foot. Thus, the well known phrase, no foot no horse, prevails.
The surfaces on which horses train and perform vary widely. Horses frequently train and compete on grass, dirt, sand, cinder, crushed stone, and sometimes on packed surfaces which nearly approach the hardness of asphalt or cement. The hardness of the training or racing surfaces can greatly increase the effective rate of loading, thus the shock and vibration, e.g., the peak g forces which the horse will experience. The shock and vibration transmitted to a horse's anatomy is intensified by metal shoes and can directly affect a horse's efficiency, athletic performance and the amount of trauma that will be experienced.
Accordingly, it can be readily understood that the potential for injury is large whenever horses train or race on hard surfaces. Horses are best trained by placing them into open paddocks and training them on forgiving yet not unstable natural surfaces. Clearly, no single factor can so greatly affect the level of stress being placed upon a horse, as can the training or racing surface and overall training program. In Thoroughbred or Standardbred racing trainers have very few alternatives, for their horses, to the racetrack for daily training.
It is known that the foot of an active unshod horse living in a natural environment will wear such that the front and back of the hoof become gently rounded. In fact, horseshoes which are initially substantially rectangular in cross-section will wear in these areas and eventually enable the combination of a horse's foot and horseshoe to assume a somewhat similar shape. Unfortunately, many conventional horseshoes are so constructed as to require replacement by the time this more natural configuration is attained. It is also known that the hoof of an active unshod horse living in a natural environment will assume a slightly concave shape in the toe area between the medial and lateral sides, as when viewed from the front, but also along both sides of the hoof between the toe and heel. This configuration permits the hoof to better slide or plane over the ground support surface during the braking phase as impact takes place, thereby reducing the effective rate of loading and the shock and vibration experienced. Further, this configuration also permits the hoof to better grab the surface during the later propulsive phase, and to break over and make a faster transition during toe-off, thus enhancing stride frequency and exhibited speed. The ability of the horse's hoof to slide somewhat can also enhance stability relative to a situation in which a horse's foot would suddenly catch or grab the ground support surface, as can happen with the use of horseshoes having rectangular configurations which possibly further include toe grabs, raised traction members or cleats. Of course, the presence of extremely loose or slippery ground can neutralize the possible adverse effects of such traction devices, and in fact, such may provide better performance and safety in such circumstances.
As explained formerly, it is known that in the unshod natural state, a horse's foot and hoof will flex and slightly widen when under load forces.
The use of relatively rigid metal or aluminum horseshoes substantially prevents this natural movement and so tends to reduce both the effective size, and the shock and vibration absorbing capability of a horse's foot. A steel horseshoe is known to be more forgiving in this regard than an aluminum horseshoe. It is believed that the occurrence of hoof cracks is sometimes caused by the flexing and widening action of the foot and hoof working against the nails associated with a substantially inflexible horseshoe. The natural wearing of the hoof is also prevented by the inflexible horseshoe which can result in contraction and inflammation of the foot.
Non-metallic materials such as plastic or rubber are sometimes used in combination with a metal horseshoe and such hybrid products are generally referred to in the industry as bonded horseshoes.
Plastic and rubber materials have been chemically and/or mechanically bonded to metal shoes to create various configurations, e.g., these materials have been used between upper and lower metal layers of a horseshoe, between the horseshoe and the hoof, on the ground engaging portion of a horseshoe, and to completely encapsulate a metal horseshoe.
Although some shock or vibration may be relieved through these alternatives, the rigidity of the metal shoe is still present as is the damaging effect of the nails.
Horseshoes made of a plastic material are known. Most, if not all, plastics horseshoes currently on the market suffer from the disadvantage that they are time-consuming and awkward to apply, particularly those that have to be assembled from a kit of parts or require special equipment. The composition of plastics horseshoes varies widely with some being as restrictive as a metal horseshoe. Some inventions teach methods where a person without farrier skills can attach the hoof covering. An equine hoof requires particular preparation prior to shoe application, with unknowledgeable trimming or rasping and handling of some equipment, disastrous results can be realized. Most Thoroughbred horses, especially those in intensive training programs can easily hurt someone not skilled in the art.
Some glue on horseshoes currently on the market attaches the shoe by use of side extensions such as tabs or fabric cuffs which extend up the sidewall of the hoof.
Gluing to a sidewall presents special problems, principally because bonds there can be subjected to very high tensile forces when a horse pivots, and bonds are usually weakest in tension. In addition, for horses with thin hoof walls, such as many Thoroughbreds have, when gluing side extensions the high heat (hoof adhesives heat up significantly when curing) can produce discomfort for the horse. The hoof wall is almost encapsulated by these extensions and adhesive creating unnatural conditions which can be detrimental to the health of the horse's foot.
It is time consuming to fit such a shoe, wasteful of material, and requires a number of parts to be supplied for each shoe. For the next shoeing, the tabs can prove extremely difficult to remove from the upper hoof wall, causing discomfort for the horse and extra time spent prepping the hoof for the fitting of new shoes.
Prior art has not recognized a product made from a plastics material which is widely accepted by trainers of performance horses. The foregoing illustrates limitations known to exist in present horseshoes. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming the limitations set forth above.
The present invention offers a solution where prior art has failed. Two of the foremost problems are addressed, the eradication of a rigid shoe and nails as the form of attachment.
Hence, the present invention teaches a novel configuration for a preferred horseshoe which conforms to the foot imitating the known configuration which healthy, active, unshod horses acquire when living in a natural environment. Further, the present invention teaches a preferred horseshoe with a degree of hardness closely resembling the natural composition of the equine hoof which permits natural flexing and widening of the foot and horseshoe when under load forces.
Accordingly, several objects and advantages of my invention are as follows:
A significant reduction of trauma and stress subjected to the horse's skeletal and muscular system when under load forces.
An improved circulatory system thus enhanced performance and health of the horse.
Due to the characteristics of the present invention a self leveling effect is achieved. As new horn is regenerated over the course of a few weeks the present invention gradually wears, resulting in a longer period of optimal biomechanics before the next shoeing. The heels are allowed to drop naturally as they grow avoiding the jammed up effect which can often lead to quarter cracks.
Another objective of the present invention is to provide an improved method of attaching a horseshoe using adhesives. The elimination of nails promotes stronger, healthier horn regeneration and removes the element of error when driving nails.
It is still another object of the present invention to considerably reduce the occurrence of diseases and detrimental conditions of the foot, e.g. laminitis, navicular syndrome, white line disease and quarter cracks.
It is yet another object of the present invention to provide a horseshoe that can be easily and efficiently attached or removed by a farrier in the field. The preferred horseshoe can be cut, rasped, sanded or ground down using regular farrier tools.
The present invention also seeks to provide a horseshoe that can easily be fitted to a foot having a given shape and width by cold forming without the need for special equipment. The simplicity and streamline nature of the present invention gives it a further advantage over prior art which is bulky and obtrusive.
It is still a further object to provide such a horseshoe which guards against dislodgment regardless of the direction of frictional force on the shoe relative to the hoof.
In field testing the present invention and method of attachment has proven its strength and resilience by 6 weeks of continued attachment on a Thoroughbred racehorse in an intensive training program. Further field testing has produced winners on racing surfaces, dirt and turf.
It is still a further object of the present invention to provide a horseshoe that is light in weight and comfortable to a horse.
These and other objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.